The process is really easy and you don’t have to think too much thing as upgrading to 5.5 which is really complicated. VMware vCenter 5.5 has many new features that we should plan the upgrade well before clicking the mouse.

I recommend that to take backup of vCenter SQL DB and if your DB recovery mode is Full, change it to simple. Depends on free space on your DB disk, the disk can be full in a minutes which no one wants it during the upgrade.

After the license page is passed, that you will see SQL DB permission error. Although your DSN configuration in ODBC is correct and your account has DB_Owner rights on your vCenter DB, you will see this error. Don’t panic the solution is really easy.

Go to your SQL server and open the properties of your vCenter account and give it a db_owner rights to MSDB and save the configuration.